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Background: Marine seaweeds are considered as a rich source of health-promoting compounds by the food and pharmaceutical industry. Hypnea musciformisis a marine red macroalga (seaweed) that is widely distributed throughout the world, including the Mediterranean Sea. It is known to contain various bioactive compounds, including sulfated polysaccharides, flavonoids, and phlorotannins. Recent studies have investigated the potential anticancer effects of extracts from H. musciformisdemonstrating their cytotoxic effects on various cancer cell lines. The anticancer effects of these extracts are thought to be due to the presence of bioactive compounds, particularly sulfated polysaccharides, which have been shown to have anticancer and immunomodulatory effects. However, further studies are needed to fully understand the molecular mechanisms that underlie their anticancer effects and to determine their potential as therapeutic agents for cancer treatment. Methods: H. musciformiswas collected from the Aegean Sea (Greece) and used for extract preparation. Transcriptome and proteome analysis was performed in liver and colon cancer human cell lines following treatment with H. musciformisseaweed extracts to characterize its anticancer effect in detail at the molecular level and to link transcriptome and proteome responses to the observed phenotypes in cancer cells. Results: We have identified that treatment with the seaweed extract triggers a p53-mediated response at the transcriptional and protein level in liver cancer cells, in contrast to colon cancer cells in which the effects are more associated with metabolic changes. Furthermore, we show that in treated HepG2 liver cancer cells, p53 interacts with the chromatin of several target genes and facilitates their upregulation possibly through the recruitment of the p300 co-activator. Conclusions: Overall, the available evidence suggests that extracts from H. musciformishave the potential to serve as a source of anticancer agents in liver cancer cells mainly through activation of a p53-mediated anti-tumor response that is linked to inhibition of cellular proliferation and induction of cell death.

Monocyte-extracellular matrix interactions have been implicated in atherosclerosis pathophysiology. Laminin, the main basement membrane protein contains cell binding domains that can be cryptic, presented only after protein modification. In the present study we evaluated monocyte attachment to laminin-1 in the presence of ATP. Monocytes were derived from either healthy volunteers or patients with diabetes mellitus type II. For the estimation of monocyte attachment to laminin the myeloperoxidase assay was used.  Monocytes derived from diabetic patients, showed an increased ability to attach to laminin (p=0.0055). The presence of ATP increased the attachment of control monocytes to laminin (p = 0.0022). On the contrary, the presence of ATP did not affect the attachment of monocytes derived from diabetic patients to laminin. Our results indicate a modified interaction between monocytes and laminin-1 in diabetes mellitus.

In the presence of NH4Cl and hypotonic solutions, Rana balcanicared cells respond by increasing their volume. The stimulation of cellular volume by hypotonicity is more rapid than that of NH4Cl, while the maximum value is less than that observed in the presence of NH4Cl. Depending on the cause of swelling, (net uptake of NH4Cl or decrease in external osmolality) cells show specific responses. The NH4Cl treatment causes a significant increase in intracellular Na+, from 5·14±0·78 to 29·84±0·47 mmoles l−1cell, while hypotonicity leads to a significant decrease of this cation, to 3·85±0·25 mmoles l−1cell in relation to the control, after 30 min of incubation of Rana balcanicaerythrocytes. In addition, amiloride significantly reverses the NH4Cl effect with respect to intracellular Na+. Both treatments cause a significant K+loss in comparison with controls. Two glycolytic enzymes glyceraldehyde phosphate dehydrogenase (GAPDH) and pyruvate kinase (PK) of Rana balcanicahaemolysate were found to respond to the NH4Cl effect by significantly decreasing their activity. Copyright © 1999 John Wiley & Sons, Ltd.